On Tue, Feb 17, 2009 at 2:02 PM, Ian Hickson <i...@hixie.ch> wrote: > For HTML5, this behaviour has been defined in more detail. The global > object is a Window object. This object is per-Document. The object > returned by the "window" attribute on that global object is actually a > WindowProxy object, which forwards everything to the "current" Window > object. However, doing this has required that I require browsers to > violate the requirement that the ES3 spec has, namely that "this" and the > object at the top of the scope chain are both the global object, because > in this model an invariant is that script cannot access the actual global > object directly, only the proxy. The HTML5 spec says: > > If the script's global object is a Window object, then in JavaScript, > the this keyword in the global scope must, contrary to the ECMAScript > specification, return the Window object's WindowProxy object. > > If it would be possible for the ECMAScript specification to have a hook > that allowed me to require this without violating the spec, that would be > great.
I don't understand. If the object you're calling Window is inaccessible from ES code, and if the object you're calling WindowProxy forwards everything to your Window, why not just relabel Window -> InternalWindow, WindowProxy -> Window? And in any case, why not just provide your WindowProxy as the global object to ES code? Why does ES need to be aware of your Window at all? The deeper problem here is that ES specs to date -- including the draft ES3.1 spec -- have not yet admitted the existence of multiple global objects. We all know we need to, but it is *way* too late to consider such a change for ES3.1. For ES-Harmony, I think we all agree we will take this step. Also, the draft module proposal at <http://docs.google.com/Doc?id=dfgxb7gk_34gpk37z9v>, proposed by Ihab Awad and Kris Kowal for ES-Harmony, relies on the introduction of a "hermetic eval" which omits the global object from the bottom of the scope chain. -- Cheers, --MarkM _______________________________________________ Es-discuss mailing list Es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
